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THE ENVIRONMENT
Various species of marine mammals have been recorded in Hong Kong waters and strandings occasionally occur. In 1986, the following strandings occurred: one Pygmy Sperm Whale (Kogia) in Tai Tam Bay, three Risso's Dolphins (Grampus) in Tolo Harbour and two Chinese White Dolphins (Sotalia) at Tap Shek Kok and Pui O, South Lantau.
More than 20 species of shark have been recorded in Hong Kong waters, mainly in the eastern and southeastern areas. Sharks have been sighted in Mirs Bay in the New Territories and at Stanley and Deep Water Bay on Hong Kong Island. Their presence is a result of the influence of warm ocean currents of the South China Sea during the summer months, especially July to September. Sharks which are common in Hong Kong, and potentially dangerous, are the Hammerhead Shark and species of the True Shark family, which can grow to more than three metres in length. Other commonly found sharks, which do not normally attack humans, include the Cat Shark and the Leopard Shark.
Plant Life
Situated near the northern limit of the distribution of tropical Asian flora, Hong Kong has an abundant variety of plant life. It is estimated that there are about 2 600 species of vascular plants, both native and introduced.
Before the introduction of conservation measures, the hillsides were becoming increas- ingly bare of trees as a result of cutting, burning and exposure to the elements. On most, the only cover was coarse grass or scrub. Now, many slopes, especially those in the water gathering grounds, have been planted with trees of both local and exotic species. These woodlands, and other areas of countryside, are protected and, with growing numbers of people spending increasing amounts of their leisure time outdoors, are being developed. In addition to making the countryside more beautiful, woodlands are important in the management of water catchments.
Remnants of the original forest cover, either scrub forest or well developed woodlands, are still to be found in steep ravines. They have survived the destructive influences of man through their location in precipitous topography and the moist winter microclimate.
Protecting the Environment
The environment of which these physical and living components form the parts is under threat from man's activities, but the specific pollution problems are similar to those encountered in comparable urbanised areas around the world. Aspects that have given rise to public concern during the year, or are considered by the government to demand special attention include:
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pollution of streams in the New Territories by animal wastes
smoke emissions from diesel-engined vehicles, which constitute 35 per cent of road traffic
excessive noise from construction, transport and air conditioning installations
water pollution blackspots such as nullahs, typhoon shelters and natural inlets of the sea
general levels of particulates in the atmosphere
the continuing need to control and dispose of the large amounts of sewage, municipal, chemical and other wastes generated by the community.
For the future, the continued vitality of topographically confined air and water systems, such as those of Deep Bay, Tolo Harbour, Junk Bay, Port Shelter and Victoria Harbour, is at risk. They are subject to new or additional pressures as a result of urbanisation which often involves entire new towns for several hundred thousand people.